2.1. Preparation of Polymer Solution
PCL solution was using tri-fluoroethanol (TFE) as a solvent. In brief, for 10% (w/v) solution, 300 mg PCL was taken in a glass vial and 3 ml of TFE was added to it. A magnetic bead was put into the vial, the vial was closed, wrapped with parafilm tape (as the solvent is volatile) and kept on a magnetic stirrer and left overnight. Similarly, 12% (w/v) and 15% (w/v) PCL solution were also prepared.